Manufacturers

Mirror Cleaning

How to clean my mirror?

First, do you really need to clean your mirrors?
If your mirrors are just dusty, at most, rinse them only. Every time
you clean your mirrors, even if you use the safest methods, you will
make some microscopic scratches on your mirrors which scatter light.
These tiny scratches degrade your telescopeís performance much more
than a little dust. Since you canít scratch mirrors if you donít
physically touch them, I rinse my mirrors about two out of every three
times I do cleaning. In general, amateur astronomers physically clean
(ie: rub them when cleaning, as opposed to just rinsing) their
telescopes too often. The large telescopes at major observatories get
incredibly dusty, dirty and even have bird-dirt on them before they are
cleaned. Given reasonable care in keeping out dust and dirt, most
people should only need to clean their telescope once a year, at most.
However, when tree sap or other residues appear on your mirror it is
time to clean!You will need the following items: a clean sink
(preferably with a sprayer), a few drops of dish washing detergent,
distilled or deionized water, one soft towel, a bowl to mix your
cleaning solution in, 500ml of 91% or higher rubbing alcohol (with NO
skin conditioners or other additives), one package of sterile surgical
cotton, a blow dryer (be sure to wipe any dust off of the dryer before
you use it).

READY! Here is the safest way Iíve found to clean
the mirrors in your telescope, I would suggest you save this for future
reference:

1) Carefully remove the mirror from the cell (the
mirror can be left in the cell if the cell is waterproof, but getting
rid of water spots around any mirror clips can be a problem) and place
it face up on a soft towel in a clean sink (donít clog the drain). Be
sure to remove anything that might fall on your mirror from the area
and keep curious children and pets away.

2) Run LUKE WARM tap
water at moderate pressure on the mirror for about 5 minutes, making
sure the entire mirror surface remains wet at all times.

3)
Remove mirror from water stream and make sure all dust and debris that
might scratch the mirror are gone, if not let it go under the water for
another 5 minutes. Use your sink sprayer to remove stubborn dirt.

4) If the mirror appears clean after this water rinsing proceed to step #7.

5)
Using a solution of 1 drop of dawn dish washing detergent mixed in one
quart of warm tap water, dip a wad of surgical roll cotton into the
solution and drag it (apply NO pressure accept the weight of the wet
cotton) in a circular motion from the center to the outside edge around
the face of the mirror, repeat if absolutely necessary, do not allow
the any of the surface of the mirror to dry.

6) Immediately rinse
the mirror for 5 more minutes with LUKE WARM tap water at moderate
pressure to ensure that all of the soap residue is rinsed away.

7) Immediately rinse the mirror with distilled or deionized water.

†Immediately
rinse the mirror off with the 91% or higher rubbing alcohol while
keeping the mirror tilted, this will strip most of the water off the
mirror.

9) Using a blow dryer at low heat, try to blow any
remaining water droplets off the edge of the mirror. Any that remain,
you may BLOT [not rub!] them away VERY GENTLY with surgical cotton or a
Q-tip.

10) Admire yourself in your in now very clean mirror, which is now ready to reinstall in your telescope.